Boiler



mg. 21 1934. M. s. HALL 1,971,068

BOILER Filed Dec. I 15. 1932 4 Sheets-Sheet 1 v P Q 03 m MoRA S. HALL INVENTOR.

ATTORNEY.

M. S. HALL Aug. EL, 1934.

BOILER Filed Dec. 15. 1932 4 Sheets-Sheet 2 -EWM on um MORA S. HALL IN VENTOR.

ATTORNEY.

M. S. HALL Aug, 21, 1934.

BOILER 4 Sheet s-Sheet 5 Filed Dec. 15. 1932 MORA S HALL INVENTOR.

ATTORNEY.

Aug. 21,1934.

M. s. HALL 1,971,068

BOILER I Filed Dec. 15. 1952 4 Sheets-Sheet 4 Mom 8. HALL INVENTOR.

ATTORNEY.

Patented Aug. 21, 1934 UNITED STATES PATENT OFFICE BOILER Mora S. Hall, Baltimore,

Md., assignor to May Oil Burner Corporation, a corporation of Maryland This invention relates to boilers for heating purposes and has particular application to the type of boilers wherein the gaseous products of combustion or other heating gases are passed through a passage or conduit surrounded by water compartments of various constructions and which are employed with low pressure steam or hot water heating systems.

Among the objects of this invention is to provide a novel interior structure for a boiler where in the gaseous products of combustion or other heating gases are caused to travel through a tortuous passage or conduit surrounded by the water and wherein a highly efficient transfer of heat from the heating gases to the water takes place.

A further object of this invention is to provide a conduit or passageway of novel construction wherein the combustion or other heating gases are passed through sections of pipes or similarly constructed lines so as to bring, at a plurality of stages during the passage of the heating gases through the conduit, streams of these gases into collision with each other and effect a thorough agitation and co-mingling of the gases, thereby counteracting any tendency for a reduction in efiiciency of heat transfer that would be occasioned by portions of the heating gases exiting from the conduit or passage before the thermal value thereof has been properly utilized.

More specifically, it is an object of this invention to provide a conduit or passage of the character heretofore described wherein the sections of tubes or similarly constructed fines are made of heat conducting material, disposed to connect gas chambers spaced from each other and to extend for a substantial distance into such cham-- bers, thereby providing at each end of said flues a substantial portion surrounded by the heated gas and a central portion surrounded by the water of the boiler, thus affording a highly elfective means for conducting heat from the gases to the water.

Other, further, and more specific objects of this invention will become readily apparent to persons skilled in the art from a consideration of the following description when taken in conjunction with the accompanying drawings wherein:

Fig. I is a central verticalsection on line l1 of Fig. II and shows a preferred form of my device applied to a vertical boiler, adapted for use with an oil burner.

FigzIl shows a horizontal section along line 22 of Fig. I, and also illustrates diagrammatically and in top plan the oil burner and the smoke pipe connected thereto.

Fig. III is a central vertical section on line 3-3 of Fig. IV and illustrates the use of my invention in a horizontal boiler.

Fig. IV is a vertical section on line 44 of Fig. III.

Fig. V is a central vertical section on line 5-5 of Fig. VI showing a modified form of my invention in use with a vertical boiler.

Fig. VI is a horizontal section on line 6-4) 01 Fig. V.

Fig. VII is a detail frag'mental view showing a modified form of disposing the inclined flues or passageways for the heating gases.

Fig. VIII is a fragmental view, in vertical section, illustrating another modified form of disposing the inclined flues or passageways for the heating gases.

Fig. IX is a fragmental view, in plan, on line 99 of Fig. VIII.

In the constructions shown inFigs. I and II, the outer shell 1 of the boiler is provided with the extension 2 forming a base and with the top wall 3. The mud ring 4 connects the outer portion of the shell 1 with the inner shell 5 at its lower extremity. The gas chamber 6 receives the combustion or other heating gases from any suitable source, such as the combustion chamber '7 in Fig. I, which gases pass through the other heating gas chambers 8 and the passageways or tubular fiues 9 connecting the chambers 8 with each other and the lower of said chambers 8 with the chamber 6 and exit through the smoke passage 10 in the upper portion of the boiler into the space surrounded by the casing 11. This casing 11 is gas tight, preferably elliptical and external to the outer shell of the boiler, and is attached to the outer shell at 12. The uptake to the chimney may be from either the upper outlet 13 or lower outlet 14, depending upon the nature of the draft and other conditions involved.

The fiues 9 are arranged in sets, each of the chambers 8 being connected to the adjacent chamber 8 by a set of these flues, the chamber 6 being connected to one of the chambers 8 by one of these sets of fiues and the smoke passage 10 also being connected to a chamber 8 by another of these sets of fiues. Each of these sets of flues 9 are preferably formed in banks of two or more fiues, the flues being of tubular form, generally of cylindrical shape, and inclined to the axis of the boiler. In the illustrations shown in Figs. I and II, the fiues 9 comprise a. central portion located either between two adjacent chambers 8 or between one of these chambers 8 and the incoming gas chamber 6 and between the smoke no passage 10 and another chamber 8, such middle portions of the flue being surrounded by water in the water compartment. These flues also have end portions projecting into the chambers 8, chamber 6 and smoke passage 10, these projecting portions being out of contact with the water and in contact with the combustion or other heating gases. The flues are preferably made of good conducting material and the portions projecting into the chamber 6, chambers 8 and smoke passage 10 are of sufficient length so as to aid in conducting heat toward the middle portions surrounded by the water and thus effecting a high efficiency of heat exchange from the combustion or other heating gases to the water in the boiler.

As shown in Fig. I, the flues 9 are preferably cylindrical, inclined to the axis of the boiler and with walls parallel to the axis of the tubes. However, it is to be understood that tubes of other configurations may be employed.

With any set of tubes, it is desirable, however, to have the streams of gas issuing from some of the tubes collide and intermingle with the streams of gas issuing from some of the other tubes so as to effect a proper mixture of the gases before exiting from any of the chambers 8. This may be accomplished as illustrated in Fig. I by having the fines 9 converging toward a restricted area or to each other. Within each chamber 8, the flues through which the gases exit overlap in spaced relation the flues through which the gases enter such compartment, thereby forcing the gases within any given chamber to travel through tortuous paths before exiting from said chamber, and. thus increasing the efliciency of heat exchange from the gases to the water surrounding the chambers. For convenience and simplicity, the flues 9 are cylindrical and straight,

but if desired tubes of other circumferential or longitudinal shapes may be used; and tubes which are bent or curved lengthwise may be employed also. It is desirable, however, that in any given set of tubes the ends through which the gases enter a chamber 8 be so positioned that the streams of gas coming through such tubes will converge toward some central space and collide and cause turbulence and forced intermingling. The result is a greater, more rapid and-more effective heat exchange between the boiler heatabsorbing surfaces and the hot gases on the inside of the chamber and the water on the outside.

My new construction also results in a lessening of the effect of the permanent, practically immobile gas film which is present at the surfaces of the heating walls exposed to the gases of combustion, and there is also a reduction of the mean hydraulic depth of the gas streams passing through the boiler. These special features in my boiler contribute to a greater heat transfer and consequently greater economy.

The base portion 2 of the casing is lined with refractory material 17 which may be either built of bricks or other molded products or else a lining of suitable, plastic, refractory material. The air inlet 18 of the oil burner 19, projects through the casing 2 and its refractory lining 1'7 into the combustion chamber '7. The upper part of the casing 2 is stayed by the bolts 20. The hot water or steam from the boiler passes by way of the outlet 21 into the heating system and the cooled water may be returned to the boiler through the pipes 22.

The flues 9 are made of somewhat heavier material than the other parts of the inner shell in order that the exposed ends will be less likely to burn off by the excessive heat of the combustion gases.

Hand holes 23 are provided for access to the interior of the gas compartment for cleaning. These holes pass through both shells l and 5 and are closed by the removable covers 24 which facilitate access to the interior. I have also provided openings and covers 25 to serve as drains or wash-out means to remove the sediment collecting on the mud ring 4. The customary fittings for boilers of this character such as safety valve, pressure gage, water glass, and test cocks are also provided.

In Figs. III and IV, I have shown the application of my invention to a boiler of the horizontal type. In this construction the" combustion chamber 26 opens into the gas chamber 27 by means of a passageway 42 cut through both the inner and outer shells 28 and 29, respectively. These shells are connected by the ring 30. The combustion chamber casing 31 is attached at 32 by a gastight connection to the outer shell of the boiler and the refractory lining 33 is built therein. The combustion or other heating gases pass through the flues 34, having the projecting ends 35 and 36, into the chambers 37. A steam dome 38 is provided at the top of the boiler, and the steam or hot water passes by way of the outlet 39 into the heating system and the cooled water may be returned through the pipe 40. The apparatus is also provided with the clean-out plugs 41, the connection 43 to the oil burner, the smoke passage 44 and smoke stack 45. A foot or stand 46 supports one end of the boiler.

In Figs. V and VI, I have illustrated a modification of my invention as applied to the vertical type. In this construction, the flues 4'7 do not project into the chambers 48 but terminate at the upper and lower bases of these chambers. In order to prevent the gases from channelling through a short passage which would reduce the efficiency of heat exchange between the gases and the water surrounding the heating gas chamber, I have provided the baflles 49 which serve to deflect the combustion gases and also assist in intermingling the gases from the various streams entering these chambers 48. This type of boiler may be made in sections which are joined by the nipples 50, and is adapted for cast iron structures. The portions designated by 51 are part of the water circulating system of this boiler. Hand holes 52 are also provided. The combustion or other heating gases from the upper chamber 48 pass to the stack by way of the outlet 53.

In Fig. VII, the flues 9 are inclined in the reverse direction from that shown in Fig. 1, and diverge from the inlet end of one of the gas compartments outwardly toward the walls of an adjacent gas compartment or chamber to the outlet end thereof. In this construction, the gases issuing from one set of flues 9 impinge against the walls of the chamber and are directed toward the central part of the chamber where they intermingle and then pass out through the next set of diverging flues.

In the modification shown in Figs. VIII and IX) the flues 9 are cylindrical and disposed so that in any given set their axes from the elements of a right circular cone having its axis preferably parallel with and in the vicinity of the axis of the boiler. In this specific construction, the streams of combustion or other heating gases issuing from the flues into chambers 8 are directed practically toward a common point and this 1,971,088 construction has certain advantages in effecting co-mingling of the gases in the streams issuing from the flues 9. The flues 9 in Figs. I and VII, and the flues 34 in Fig. III are illustrated in banks 6 of four on each side of any given set, with the fluesin any given bank practically parallel to each other. In such arrangement, there is no convergence of the streams toward each other in any bank of flues, but the streams issuing from flues of one bank converge toward those from the flues of another bank of the same set.

My new boiler may be used with combustion apparatus employing either fluid or solid fuel, but for purposes of illustration I have shown in Fig. II the application with this boiler of a fuel-oil burner of the pressure, atomizing gun-type. My new boiler is also adapted for use with oil burners of the rotary type, in which case the refractorylined combustion chamber may be omitted. Under such conditions, the combustion takes place at substantially the level of the lower end of the water compartment of the boiler.

With boilers such as shown herein, if solid fuel is used the combustion chamber is omitted and a grate is placed substantially at the level of the mud ring. An ash-pit door is also provided in the lower projecting part of the outer casing and a fuel door in the gas chamber.

The present invention is not limited to the specific details set forth in the foregoing examples which should be construed as illustrative and not by way of limitation, and in view of the numerous modifications which may be effected therein without departing from the spirit and scope of this invention, it is desired that only such limitations be imposed as are indicated in the appended claims.

I claim as my invention:

1. In a boiler, awater compartment and a heating-gas compartment surrounded by said water compartment, said heating-gas compartment having in series alternating chambers and passageways, each of said chambers being connected with the adjacent chamber by means of a plurality of said passageways extending in an oblique direction from a position near the central portion of one chamber to a position near the wall of the other chamber and said passageways having their ends projecting into said chambers.

2. In a boiler, a water compartment and a heating-gas compartment surrounded by said water compartment, said heating-gas compartment comprising a plurality of tubes and a plurality of chambers spaced from each other and connectedby said tubes, said tubes having their ends projecting into said chambers, a portionot each of said tubes being disposed 'for direct contact with the water of said water compartment and said tubes being disposed to receive heating gases and to discharge streams of said heating gases against each other into one of said chambers. then to receive the gases from said latter chamber and discharge streams thereof against each other into a succeeding chamber.

3. In a boiler, a water compartment and a heat- S-Eas compartment surrounded by said water compartment, said heating-gas compartment having in series alternating chambers and sets of tubes, said tubes having their ends projecting into said chambers and the outlet end of each of said tubes being inclined toward the central portion of the chamber into which it opens.

4. In a boiler, a. water compartment and a heating-gas compartment surrounded by said water compartment, said heating-gas compartment comprising a plurality of tubes and a plurality of chambers spaced from each other and connected by said tubes, said tubes being of heatconducting material having their ends projecting into said chambers and their intermediate portion disposed for direct contact with the Water of the water compartment, and said tubes being disposed to receive heating gases and to discharge streams of said heating gases against each other into one of said chambers, then to receive the gases from said latter chamber and discharge streams thereof against'each other into a succeeding chamber.

5. In a boiler, a water compartment and a heating-gas compartment surrounded by said water compartment, said heating-gas compartment having in series alternating chambers and sets of tubes, the outlet end of said tubes being inclined toward the central portion of the chamber into which it opens and a portion of each of said tubes being disposed for direct contact with the water of the water compartment and means comprising bafiles within said chambers for efiecting a tortuous path for gases passing through said heating-gas compartment.

6. In a boiler, a water compartment and a heating-gas compartment surrounded by said water compartment, said heating-gas compartment having in series alternating chambers and sets of tubes, said tubes having their ends projecting into said chambers, the outlet end of each of said tubes being inclined toward the central portion of the chamber into which it opens and a portion of each of said tubes being disposed for direct contact with the water of the water compartment, and the axes of the tubes in each set forming substantially the elements of a conical surface the axis of which is in the vicinity of and substantially parallel to the axis of the boiler.

7. In a boiler, a water compartment and a heating-gas compartment surrounded by said water compartment, said heating-gas compartment having in series alternating chambers and sets of fines, each of said chambers being connected with the adjacent chamber by means of a set of said fiues extending from a. position near the wall of one chamber to a position near the central portion of the other chamber, said flues being disposed in tiers of two banks and symmetrically on both sides of a median plane ofsaid boiler, the axes of said flues in each bank being substantially parallel, said flues being disposed to receive heating gases and to discharge streams of heating gases against each other into one of said chambers then to receive the gases from said latter chamberand discharge streams thereof against each other into a succeeding chamber, a

' gas outlet connecting the last chamber of said series with a smoke box and comprising an eccentrically disposed external gas-tight jacket partly surrounding the outer shell of said boiler, said jacket being adapted for connection to the chimney of the boiler.

MORA S. HALL. 

